Pump group

ABSTRACT

A pump group has an impeller, a shaft having an impeller end on which the impeller is mounted and a control end for receiving a rotary control action, and a pump body having an impeller body housing the impeller, a shaft body partially housing and supporting the shaft in free rotation, and a control body integrally connected to the shaft body and having a control cavity through which the control end extends axially. The pump group has a mechanical drive having a rotating member mounted in free rotation on the control body for receiving an external action from an external group, a rotating drum integrally connected to the control end, and a control device configurable in an engagement configuration, in which the rotating member and the rotating drum are engaged to rotate together, and a disengagement configuration, in which the rotating member is separate from the rotating drum rotating individually.

The present invention concerns a pump group for an engine cooling systemof a vehicle. In particular, this cooling system is specific to coolingthe engine, for example, but not necessarily, of the internal combustiontype, of the vehicle.

In the state of the art there are many known embodiments of pump groupsfor an engine cooling system that differ from each other in dimensionsand type of drive.

Specifically, the pump group object of the present invention is placedin this context, comprising a mechanical-type drive. In other words, thepump group object of the present invention comprises a mechanical drivewhich controls the rotary movement of the impeller comprised therein,thus controlling the movement of the cooling liquid which flows into thecooling system to which the pump group may be fluidically connected.

In the state of the art there are many technical solutions of pumpgroups in which said mechanical drive is suitable to receive a rotarycontrol action from a group external to the pump group in turn comprisedin the vehicle, for example by means of specific transmission elements,such as belts and/or chains, and transform it in turn into a rotaryaction of the impeller.

According to some embodiments, the mechanical drive is a pulley, anelectromagnetic pulley, a pulley containing a clutch group, for examplea centrifugal clutch.

According to the preferred known embodiments, the mechanical drive isdirectly mounted on the shaft on which is mounted the impeller.

In the solutions of pump groups belonging to the state of the art, theproblem is therefore encountered of needing a driving shaft that issuitable to support the forces and inertia of the mechanical drive.

The object of the present invention is to provide a pump group for anengine cooling system of a vehicle, for example for an internalcombustion engine, which addresses the aforesaid problems. Inparticular, the object of the present invention must be contextualizedto the sector of reference, i.e. the automotive sector, and thus providea pump group with compact dimensions and simple production suitable tobe housed in the vehicle, preferably near the engine comprised therein.

Such an object is achieved by a pump group according to claim 1. Theclaims dependent thereon refer to preferred variant embodiments, havingfurther advantageous aspects.

The object of the present invention is hereinafter described in detailwith the aid of the accompanying figures, wherein:

FIGS. 1a and 1b illustrate two perspective views of a pump group inaccordance with the present invention, according to a possibleembodiment;

FIG. 2 shows a side view of the pump group as shown in FIGS. 1a and 1 b;

FIG. 3 shows a longitudinal section of the pump group in FIG. 2;

FIG. 4 illustrates a perspective view in separate parts of the pumpgroup in FIGS. 1a and 1 b;

FIG. 5 illustrates a longitudinal sectional view in separate parts ofthe pump group in FIGS. 1a and 1 b.

In the aforesaid figures, a pump group for an engine cooling system of avehicle, preferably for cooling the engine, for example an internalcombustion engine, is indicated collectively at reference number 1.

Specifically, the pump group 1, object of the present invention, issuitable for moving a predefined quantity of cooling liquid in the ductsof an engine cooling system of an engine. Preferably said cooling liquidis a liquid solution based on water and glycol and/or oil. Specifically,the present invention is not limited to the nature of the type ofcooling liquid.

The pump group 1, object of the present invention, preferably extends inlength with respect to an axis X-X.

The pump group 1, object of the present invention, comprises an impeller2 rotatable with respect to said axis X-X. In other words, said impeller2 has a center of rotation that lies on said axis X-X.

Preferably, the impeller 2 is of the radial type, being specially shapedto perform a suction action on the cooling liquid, preferably in theaxial direction, and to perform a thrust action, preferably in theradial direction.

In other words, the impeller 2 is specifically suited to move a quantityof cooling liquid in the engine cooling system.

According to the present invention, moreover, the pump group 1 comprisesa shaft 3 extending in length along the axis X-X.

The shaft 3 comprises an impeller end 32 on which the impeller 2 isintegrally mounted and a control portion 31 suitable to receive a rotarycontrol action from a mechanical drive 5 which is in turn comprised inthe pump group 1 as described in detail below.

According to the present invention, the pump group 1 comprises a pumpbody 4 supporting and housing the respective components of the pumpgroup 1. In particular, in effect, the pump group 1 is suitable to befluidically connected to the respective ducts of the engine coolingsystem of a vehicle.

According to the present invention, the pump body 4 is divided into aplurality of specific members/bodies:

an impeller body 42 which houses the impeller 2 in a specially shapedimpeller chamber 42;

a shaft body 43 that partially accommodates and supports the drivingshaft 3 in free rotation (which in the attached figures is showncomprising the respective shaft bearing assembly);

a control body 44 comprising a control cavity 44 through which thedriving shaft 3 extends in such a way that the control end 31 thereofprotrudes axially from said control body 44.

In accordance with the present invention, the control body 44 isintegrally connected to the shaft body 43.

According to the present invention, the pump group 1 comprises amechanical drive 5 having the purpose of controlling the rotation of theshaft 3 by receiving an external action from an external group, forexample the motor group, to which it is connected by means of atransmission group or a transmission element, such as a belt, a chain ora kinematic gear mechanism.

In particular, as is clearly visible in the accompanying figures, saidmechanical drive 5 is suitable to engage the shaft 3 being mounted onsaid control body 44.

The mechanical drive 5 in effect comprises:

l) a rotating member 51 mounted in free rotation on the control body 44with respect to the axis X-X, wherein the rotating member 51 is suitableto receive an external action from an external group which moves it inrotation, for example from a transmission element, or belt;

m) a rotating drum 52 integrally connected to the control end 31 of theshaft 3;

n) a control device 53 configurable in an engagement configuration inwhich the rotating member 51 and the rotating drum 52 are mutuallyengaged to rotate together and a disengagement configuration wherein therotating member 51 is separate from the rotating drum 52 rotatingindividually.

According to a preferred embodiment, the rotating member 51 has asubstantially axial-symmetrical shape with respect to the axis X-X.

According to the present invention, the rotating member 51 has asubstantially annular shape.

In particular, according to a preferred embodiment, the rotating member51 comprises at a first axial end an operating cavity 510 in which therotating drum 52 and partially the control device 53 are housed.

In addition, according to a preferred embodiment, the rotating member 51comprises, at a second axial end, a body housing cavity 511, in whichthe control body 44 is at least partially housed. For example, in theaccompanying figures, the entire control body 44 is housed in the bodyhousing cavity 51.

According to a preferred embodiment, the rotating member 51 comprises acap 518 suitable to close the operating cavity 510 preventing accessthereto from the outside, for example protecting it from the elements.

According to a preferred embodiment, the rotating member 51 comprises anouter perimeter wall 515 that extends parallel to the axis X-X; thiswall is thus located in a distal position from said axis X-X.

Preferably, the perimeter wall 515 is suitable to be engaged by anexternal group to receive the external rotational action; preferably onsaid perimeter wall 515 a drive belt may thus be wound.

According to the present invention, the rotating member 51 furthercomprises an inner wall 513 which extends parallel to the axis X-Xsuitable to engage the control body 44 by means of a bearing group 512(preferably in turn comprised in the mechanical drive 5); thus,preferably, the inner wall 513 is in a position proximal to said axisX-X.

According to a preferred embodiment, the rotating member 51 comprises aradial wall 514 that extends radially to said axis X-X to joinintegrally the inner wall 513 with the outer perimeter wall 515.

In other words, the radial wall 514 axially separates the operatingcavity 510 and the body housing cavity 511. The operating cavity 510 andthe body housing cavity 511 are radially defined by the inner wall 513and by the outer perimeter wall 515.

According to a preferred embodiment, the rotating drum 52 is integrallymounted on the shaft 3, on the control end 31 of the shaft 3, whichprotrudes from the control body 44.

Preferably, the rotating drum 52 has a substantially radial extensionwith respect to the shaft 3.

According to a preferred embodiment, the control device 53 performs anaction in the axial direction which allows the configuration changebetween the engagement configuration and the disengagement configurationand vice versa.

According to a preferred embodiment, the control device 53 comprisesfirst control members 531 housed in the control body 44 and secondcontrol devices 532 housed on the control drum 52.

Said first control members 531 and said second control members 532 aremagnetically sensitive to each other.

Preferably, the first control members 531 are of the type comprisingsensors or coils of electrical or electronic type adapted to produce amagnetic field, while the second members 532 are of the type comprisingmagnetically sensitive elements suitable to undergo the action of saidmagnetic field produced by the first control members 531.

According to a preferred embodiment, the second control members 532comprise a disk element 532′ fitted axially movable on the driving shaft3.

According to a preferred embodiment, the second control members 532comprise moving elements 532″, housed on the drum element 52, which aremagnetically sensitive.

Preferably, the moving elements 532″ engage the disk element 532′ insuch a way as to control its axial position between an engagementposition in which the rotating member 51 that drives it in rotationtransmits via the moving elements 532″ the rotary motion to the drum 52(corresponding to the engagement configuration), and a disengagementposition in which it is axially separated from the rotating member 51,which then rotates in solitary mode (corresponding to the disengagementconfiguration).

According to a preferred embodiment, said moving elements 532″ compriseelastically resilient members adapted to perform normally an action onthe disk element 532′ in such a way as to keep it in the disengagementposition, and adapted to perform an action on the disk element 532′which brings it into an engagement position only on command of themagnetic action produced by the first control members 531.

According to a preferred embodiment shown in the accompanying figures,the moving elements 532″ are elastic wing elements.

According to a preferred embodiment, the disk element 532′ in theengagement position, which corresponds to the engagement configuration,performs a friction action on the rotating member 51. In other words,the action of mutual engagement between the disk element 532′ and therotating member 51 is due to the friction between the two components.Preferably, the disk element 532′ has portions with friction materialspecifically designed for this purpose.

Preferably, therefore, the mechanical drive 5 is suitable to be axiallyfitted on the control body 44 being specially shaped to accommodate andoperate also with the control portion 31 of the shaft 3.

In particular, according to a preferred embodiment, the control body 44has a substantially asymmetrical shape comprising a central tubularportion 441 having axial extension, wherein within the central tubularportion 441 is obtained the control opening 440.

According to a preferred embodiment, the control opening 440 issubstantially complementary in dimension to the shaft 3. Preferably, dueto the central tubular portion 441, the shaft 3 is maintained in theaxis X-X by the walls that define said control opening 440.

Preferably, the rotating member 51 is mounted outside the centraltubular portion 441; in particular, the bearing unit 512 is housed onthe central tubular portion 441.

Moreover, according to a preferred embodiment, the control body 44further comprises a support portion 443 distal from the axis X-X,suitable for engaging the shaft body 43.

According to a preferred embodiment, the support portion 443 has adimension substantially complementary to the body housing cavity 511.

Moreover, according to a preferred embodiment, the control body 44,further comprises a radial portion 442 extending substantially radiallyto said axis X-X to join integrally the central tubular portion 441 andthe support portion 443.

According to a preferred embodiment, the control body 44 is a singlepiece. Preferably, the control body 44 is made as a single element outof steel alloy.

According to a preferred embodiment, the control body 44 has anincreasing cross-section starting from the proximal portions to the axisX-X, i.e. from the central tubular portion 441, to the distal portionsfrom the axis X-X, i.e. the support portion 443.

Preferably, the central tubular portion 441, the radial portion 442 andthe support portion 443 are connected to each other with curvedprofiles. According to a preferred embodiment, the central tubularportion 441, the radial portion 442 and the support portion 443 do nothave sharp edges.

Preferably, the first control members 531 are housed in said supportportion 443.

According to the present invention, it is also possible to envisageembodiments of dual-type pump groups, i.e. including an electric drivein addition to the described mechanical drive.

According to this preferred embodiment, the electric control driveengages in turn the shaft 3 to guide it in rotation, preferably in aconfiguration wherein it is not driven in rotation by the mechanicaldrive 5 (preferably controlled in the disengagement configuration).

According to a preferred embodiment, said electric control drive,comprises an electric control motor and is positioned between theimpeller 2 and the mechanical drive 5.

Preferably, the pump body 4 comprises an electric drive body that housessaid electric motor, positioned between the shaft body and the controlbody or between the impeller body and the shaft body.

Innovatively, the pump group that is object of the present inventionclearly satisfies the purpose of the present invention.

Advantageously, the pump group that is the object of the presentinvention comprises a mechanical drive and a pump body, respectively,specially shaped to prevent all the forces and inertia of the mechanicaldrive from being discharged on the shaft. Advantageously, the shaft maybe sized according to the actions it must undergo. Advantageously, theshaft has dimensions, and in particular diameter, smaller than theshafts of the known pump groups.

Advantageously, the pump group has a simple and compact shape anddimensions.

Advantageously, in the pump group that is the object of the presentinvention, the pump body and mechanical drive are specially shaped insuch a way that the mechanical drive is kept aligned along the axis.

Advantageously, the pump body has a high structural strength.

Advantageously, the control body is suitable to make full use of thespace inside the rotating member, i.e. inside the mechanical drive.

Advantageously, the mechanical drive has a simple, precise and reliableoperation when switching between the engagement configuration and thedisengagement configuration.

Advantageously, an embodiment of a dual pump group that makes full useof the aforesaid advantages is foreseeable.

It is clear that a person skilled in the art, in order to meetcontingent needs, may make changes to the pump group, all containedwithin the scope of protection as defined by the following claims.

Moreover, each variant described as belonging to a possible embodimentmay be implemented independently of the other variants described.

1-14. (canceled)
 15. A pump group for an engine cooling system of avehicle, the pump group comprising: an impeller rotatable with respectto an axis (X-X) suitable to move a quantity of cooling liquid into theengine cooling system; a shaft extending in length along the axis (X-X)and comprising an impeller end, the impeller being integrally mounted onthe impeller end, and a control end adapted to receive a rotary controlaction; and a pump body comprising: an impeller body housing theimpeller in an impeller chamber; a shaft body partially housing andsupporting the shaft in free rotation; and a control body integrallyconnected to the shaft body, the control body comprising a controlopening through which the shaft extends so that the control endprotrudes axially from said control body, wherein the control body isaxial-symmetrical in shape and comprises: a central tubular portionhaving axial extension, the control opening being obtained inside thecentral tubular portion and having a dimension complementary to theshaft, so that the shaft is kept in axis (X-X) by walls defining saidcontrol opening; a support portion located in a distal position from theaxis (X-X) adapted to engage the shaft body; a radial portion extendingradially to said axis (X-X) to integrally join the central tubularportion and the support portion; and a mechanical drive controllingrotation of the shaft, the mechanical drive comprising: l) a rotatingmember mounted on the control body outside the central tubular portion,in free rotation with respect to the axis (X-X), wherein the rotatingmember is suitable for receiving an external rotary action from anexternal group comprised in the vehicle; m) a rotating drum integrallyconnected to the control end of the shaft; and n) a control deviceconfigurable in an engagement configuration, in which the rotatingmember and the rotating drum are mutually engaged to rotate together,and a disengagement configuration, in which the rotating member isseparate from the rotating drum and rotates individually.
 16. The pumpgroup of claim 15, wherein the rotating member is axial-symmetrical inshape in relation to the axis (X-X) and comprises, at a first axial end,an operating cavity, the rotating drum and, partially, the controldevice being housed in said operating cavity and, at a second axial end,a body housing cavity, the control body being at least partially housedin said body housing cavity.
 17. The pump group of claim 16, wherein therotating member comprises a plug adapted to close the operating cavitypreventing access from outside.
 18. The pump group of claim 15, whereinthe rotating member comprises: an outer perimeter wall, located in adistal position from the axis (X-X), extending parallel to the axis(X-X), wherein said outer perimeter wall is suitable for being engagedby an outer unit to receive an external rotational action; an innerwall, located in a position proximal to the axis (X-X), extendingparallel to the axis (X-X), wherein said inner wall engages the controlbody by a bearing group; and a radial wall extending radially to saidaxis (X-X) to integrally join the inner wall with the outer perimeterwall.
 19. The pump group of claim 15, wherein said support portion has adimension complementary to the body housing cavity.
 20. The pump groupof claim 15, wherein the control device performs an action in axialdirection which allows changing from the engagement configuration to thedisengagement configuration and vice versa.
 21. The pump group of claim15, wherein the control device comprises first control members housed inthe control body and second control members housed on the rotating drum,wherein the first control members and the second control members aremagnetically sensitive to each other.
 22. The pump group of claim 21,wherein the first control members comprise electronic sensors suitableto produce a magnetic field, while the second control members comprisemagnetically sensitive elements suitable to undergo an action of saidmagnetic field produced by the first control members.
 23. The pump groupof claim 22, wherein said second control members comprise a disk elementfitted axially movable on the shaft, and moving elements housed on therotating drum, magnetically sensitive, engaging said disk element tocontrol its axial position between an engagement position, in which therotating member drives it in rotation transmitting via the movingelements a rotary motion to the rotating drum, and a disengagementposition in which the disk element is axially separated from therotating member.
 24. The pump group of claim 23, wherein said movingelements comprise elastically resilient members adapted to normallyperform an action on the disk element to keep it in the disengagementposition, and to carry out an action on the disk element which brings itinto the engagement position only on command of a magnetic actionproduced by the first control members.
 25. The pump group of claim 23,wherein the disk element in the engagement position, which correspondsto the engagement configuration, performs a friction action on therotating member.
 26. The pump group of claim 15, further comprising anelectric control drive, adapted to engage the shaft to guide it inrotation, wherein said electric control drive comprises an electriccontrol motor and is positioned between the impeller and the mechanicaldrive, wherein the pump body comprises an electric drive body housingsaid electric control motor, positioned between the shaft body and thecontrol body or between the impeller body and the shaft body.
 27. Thepump group of claim 15, wherein the external group is a transmissionelement.